Srinagar, Aug. 9 -- COVID-19 cases are climbing again in the United States this summer, fueled by two fast-spreading variants known as NB.1.8.1 (nicknamed "Nimbus") and XFG ("Stratus"). The Centers for Disease Control and Prevention (CDC) reports rising infections in 40 states, particularly across the Mid-Atlantic, Southeast, South, and West Coast. Nine states remain stable, but none are seeing declines. While case numbers are still far lower than during past surges, emergency room visits for COVID-like symptoms are up.

Nimbus has become the dominant strain nationwide, known for causing an intense sore throat often described as feeling like "razor blades." Stratus is now the third most common variant and is spreading quickly. Experts fro...